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2543 Uppsatser om Renewable energy sources - Sida 46 av 170

?What is going on??: En studie av internationella studenters informationsbehov på Högskolan i Borås

The purpose of this Bachelor?s thesis was to examine the information needs of the international students at the University of Borås. A further aim was to examine the types of information sources the international students was using to satisfy their information needs and the environmental factors keeping them from achieving this. This was done through focus group interviews with international students from four different countries ranging from the ages 20 ? 35.

Val av komplementmaterial för våtkompostering av klosettvatten

Emissions of insufficiently treated wastewater, mainly blackwater (i.e. wastewater from toilets), contributes to the eutrophication of lakes and seas. At the same time, blackwater is a fraction with a low content of heavy metals and, after sanitization, it can recirculate plant nutrients to arable land using the liquid composting treatment method. Liquid composting means that organic material is degraded under aerobic conditions. For sanitization, the blackwater needs to be treated together with energy-rich complementary material.

Turbinkretspump system - Kraftvärmeverket i Borås

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.

Solel från ljudbarriär : längs Annetorpsvägen i Hyllie, Malmö

City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers.

Torrefaction of biomass : a comparative and kinetic study of thermal decomposition for Norway spruce stump, poplar and fuel tree chips

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

Utvärdering av laddningskoncept för lastbilsbatterier

When drivers overnight in the truck lots of electric energy is consumed by heaters, fans, lights and other extra equipment. If the engine is not running, this energy is taken from the lead/acid batteries of the truck which then needs to be recharged during operating hours. The fact that the charge acceptance of the lead/acid batteries is dependent on the temperature makes it hard to fully recharge the batteries at lower temperatures. A negative charge balance can lead to starting problems within a few days use in cold climate.In this thesis work, the effects of different battery charging concept are evaluated on the most common Scania battery (175Ah). A battery model is implemented in Matlab and some simulations of charging are made.

Sjuksköterskestuderandes biblioteks- och informationsanvändning: Två olika världar.

The main purpose of this study is to investigate how student nurses seek and use information and libraries. Furthermore, I want to know how they think information can be used in their future occupation. Seven student nurses were included in the study. A qualitative method with personal interviews was used. The analysis of the empirical material was made according to a socio-cultural perspective.

Utvärdering av möjligheten att tillvarata energi ur processvatten : En undersökning gjort vid Olofsfors AB på uppdrag av UMIA AB.

The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.

Döden som social överlevnad. Keltiskt människooffer under järnåldern

This essay concerns the Celts during the Iron Age, and their ritual practice in human sacrifice. The method applied is an eclectic historic-critic reading of the few classical sources that exist together with archeological material and scholars conclusions of literal sources and archeological material. The hypothesis is that human sacrifice in the Celtic realm not is to be seen as a primitive act of violence, but that it filled a social function to preserve society and the Celtic way of life.The question this essay strives to answer is Which function/s do human sacrifice fill in a Celtic context during the Iron Age? The question is analysed with the aid of Radcliffe-Brown?s and Catherine Bell?s theories on ritual, as well as Malcolm Chapman?s postmodern ideas of the conception of the Celtic. The conclusion of the essay is that the prime functions of Celtic human sacrifice are to preserve society and the Celtic social way of life, combined with an aim to eliminate disturbing elements in that same society, such as crime and individuals who did not fit in to the social community..

Den som vet bäst vinner mest - Om information i butik och hur den används.

When in the process of buying a product based high effort behavior, the consumer needs information to decide on which product that best satisfies their need. There is a wide arrange of sources where this could be found. One of the most important, due to the great influence it has on consumer choice, is in-store communications. This is also one of the least developed sources. It is not uncommon that the only facts that can be acquired are found on product packaging and from contact with the store´s staff.

Byggnadsintegrerade solcellssystem : Solceller som byggnadsmaterial

This thesis aims to identify the building integrated photovoltaic solutions available in the market with respect to general pros and cons of different systems and a technical description of there attachment system. Investigate and provide examples of various building integrated photovoltaic solutions in Sweden and describe the experiences and results of these projects.The methods used to obtain relevant information are interviews with individuals involved in significant projects and a thorough search of different solutions from solar suppliers.The conclusion is that solar energy is needed for a sustainable society. There are endless opportunities regarding BIPV, with many companies with different products and individual solutions. But so far it?s not so customary in Sweden.

Löpmagsförskjutning hos mjölkkor : en besättningsutredning för att identifiera riskfaktorer för metaboliska störningar

The purpose of this study was to find possible explanations to why the studied herd had an increased incidence of abomasal displacements. The incidence of abomasal displacement in the herd was three times higher than the incidence of an average Swedish herd. The cows in this study were fed a total mixed ration. The different parameters studied were: energy content in food, nutritional content in food, body condition scoring, concomitant other diseases, and blood parameters of glucose, fructosamine, cholesterol, insulin, betahydroxybutyrat and free fatty acids. The author?s suggestions to decrease the problems are to decrease the energy content in the TMR to lower the cows? body condition scores in the dry period and changing the content in the TMR to increase the amount of NDF and adding structure in the form of chopped straw.

Kombinerat system för ventilation och rumsuppvärmning : Parameterundersökning i simuleringsmodell för takvärmesystem

A large amount of our time is spent indoors in an artificial climate. To make the experience pleasant there are requirements on the ventilation and the heating system. At the present time the most common form of heating is a radiator system complemented with a ventilation system. A ceiling heating system with combined heating and ventilation can replace the two separated systems. The benefit with a ceiling heating solution is that it saves space since the radiator system is no longer needed.

Spårtaxisystem i Uppsala

An increased awareness about the global warming has created a demand for more information on how the climate is affected by different activities.This master thesis was initiated by Tricorona, a Swedish company that offers its customers analysis and calculation of their climate impact. Tricorona also supplies climate neutralisation with CERs, in accordance with the Kyoto protocol and controlled by the UN. This work demands updated emission factors for greenhouse gases. An emission factor gives information about the greenhouse gasintensity of a service or a product [kg CO2-eq./ functional unit].The purpose of this thesis is to examine how electricity, district heating, hotels, taxis, food and materials affect the climate and how emission factors for these areas can be calculated.This was done by reviewing and comparing different studies and by interviewing experts. The information was evaluated and recommendations on calculations and emission factors were made.The consumption of energy is the main source of greenhouse gas emissions for district heating, electricity, hotels, taxis and materials.

Förutsättningar för att utnyttja solceller i Sala-Heby relaterat till ekonomiska stöd

There have been several projects with solar installations in Sweden, and Sala-Heby Energi (SHE) wanted to create a solar plant. The question answered in this thesis is whether it is economically viable to create such a source of sustainable, renewable energy. The plant would be built with the help of the financial effort from 120 customers. This economic union would sell the electricity to the SHE, for SEK 4.50 per kWh up to a certain level over a period of 10 years. It would be a long term commitment to environmentally friendly electricity, using solar cells which convert sunlight directly into electricity.In year 2009 there was introduced a new state aid for photovoltaic systems, to create an increased and continuing interest in solar cells.

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